A stent may be loaded onto a catheter inner tube either from the distal end of the inner tube or from the proximal end of the inner tube. When the stent is loaded from the distal direction, however, the tip of the catheter may interfere with the stent. To avoid obstruction from the tip, the stent as loaded must have an opening wide enough to allow passage of the tip therethrough which causes issues in device performance. When the stent is loaded from the proximal direction, the stent may be obstructed by any proximal bumpers present on the inner tube. Typically, a bumper is provided proximal to the stent receiving region of the catheter inner tube to aid in delivering the stent from the catheter. To avoid obstruction from the bumper, the stent as loaded must have an opening wide enough to allow passage of the bumper therethrough, again causing issues with device performance.
Once the stent has been loaded on the catheter, a retractable sheath is typically placed over the stent. A number of devices for retracting a retractable sheath are known in the art. Patents disclosing retractable sheaths include U.S. Pat. No. 5,772,669 and U.S. Pat. No. 5,868,755. With many retraction systems, it is necessary to move a portion of the manifold by a distance at least equal to the length of the loaded stent to retract the sheath.
While a number of patents such as U.S. Pat. No. 6,090,035, U.S. Pat. No. 6,018,857 and U.S. Pat. No. 5,911,452 have dealt with the issue of stent loading, there remains a need for innovative methods of loading self-expanding stents onto catheters as well as for innovative catheters that facilitate this stent loading. There also remains a need for innovative catheters having retractable sheaths and sheath retraction mechanisms having a mechanical advantage to facilitate sheath retraction.
All U.S. patents, patent applications and other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention, a brief summary of various embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.